CN101384469B - Vehicular steering control device - Google Patents

Abstract

The present invention provides a vehicular steering control device (10), which comprises steering force applying means (15, 30) for applying a steering force to front wheels (5, 6), and transverse force detecting means (42) for detecting the individual transverse forces of the front wheels and rear wheels (7, 8). The steering force applying means apply a converging steering force to steer the front wheels in a direction to converge yaw vibrations, in case the ratio of a transverse force (Fr) of the rear wheels to a transverse force (Ff) of the front wheels becomes such a ratio as may cause the yaw vibrations of a vehicle (1).

Description

Vehicular steering control apparatus

Technical field

The present invention relates to be used for the control convenience of automatically controlled turning to (power steering) equipment, more specifically, relate to the automatically controlled turning facilities that is used for vehicle.

Background technology

Vehicle such as automobile uses electric power steering apparatus, and it will turn to assist torque to be applied to the steering hardware that comprises front-wheel by turning to the torque actuated electrical motor according to what applied by the chaufeur of operation steering handwheel or working team.In this electric power steering apparatus, disclose as patent documentation 1, carry out phase compensation (that is decay control) according to the expected value that turns to assist torque to be supplied to the basic auxiliary current of electrical motor that is applied.Utilize this structure, can consider attenuation components, this allows to improve the convergence that turns to.

Patent documentation 1: Japanese Patent Application Publication 2004-203122 number

Summary of the invention

The problem that the present invention solves

In order to improve the convergence of vehicle as mentioned above, a kind of possible means are to strengthen aforementioned decay control.But if strengthen decay control, then chaufeur is experienced variation to turning to of steering handwheel.More specifically, experience than viscous or heavy weight when the enhancing of decay control has brought the operation steering handwheel, and brought vehicle not as the desired impression that turns to like that of chaufeur.On the other hand, if weaken decay control, then based on vehicle feature (or structure etc.), it is coupled to each other to turn to vibration and yaw to vibrate, the convergence that this can the deterioration overall vehicle.That is, turn to the phase place of vibration and the phase place of yaw vibration to become anti-phase relation, may strengthen the vibration that is applied to overall vehicle.

Consider the problems referred to above, thereby the purpose of this invention is to provide a kind of Vehicular steering control apparatus, the constringent convergence that improves vehicle simultaneously that it can turn in raising.

The means of dealing with problems

(1) Vehicular steering control apparatus

Above purpose of the present invention can realize that it is provided with by a kind of Vehicular steering control apparatus: the steering effort bringing device, and it is used for steering effort is applied to front-wheel at least; With the transverse force detecting device, it (for example is used to detect described front-wheel, front tyre) and trailing wheel (for example, rear tyre) every person's transverse force, if the ratio of the described transverse force of the described transverse force of described trailing wheel and described front-wheel becomes the ratio of the yaw vibration that may cause in the vehicle, then described steering effort application devices will be restrained steering effort and will be applied to described front-wheel, and described convergence steering effort makes described front-wheel steering on the direction of described yaw vibration convergence.

The vehicle according to the invention steering control apparatus if the ratio of the transverse force of the transverse force of trailing wheel and front-wheel becomes the ratio of the yaw vibration that may cause in the vehicle, then can make front-wheel steering, makes the yaw vibration restrain.Thus, even even the transverse force that produces on trailing wheel may cause in the situation of front-wheel vibration or the vehicle may be taken place under the situation of yaw vibration, it is coupled to each other also can to prevent to turn to vibration and yaw to vibrate.This can cause the convergence of the vibration of front-wheel.That is, can under the constringent situation that raising turns to, improve the convergence of vehicle.

Incidentally, " front-wheel " of the present invention represents to be positioned at respect to the travel direction of vehicle the wheel of relative front side, and " trailing wheel " is positioned at the wheel of relative rear side with respect to the travel direction of vehicle.

Aspect of Vehicular steering control apparatus of the present invention, described steering effort application devices (i) is if turned to be in and rotated or the incision state by what the chaufeur of described vehicle carried out, then compare with the situation that the described transverse force of described front-wheel does not become the described ratio that may cause the described yaw vibration in the described vehicle with the described transverse force of described trailing wheel, with the steering effort that on neutral direction, makes described front-wheel steering that applies as described convergence steering effort, if and (ii) turn to be in and return or inverted status by what the described chaufeur of described vehicle carried out, then do not become the situation that may cause the described yaw vibration in the described vehicle with the described transverse force of described front-wheel and compare, with the steering effort that on the end direction, makes described front-wheel steering that applies as described convergence steering effort with the described transverse force of described trailing wheel.

According in this respect, if the ratio of the transverse force of the transverse force of trailing wheel and front-wheel becomes the ratio of the yaw vibration that may cause in the vehicle, then with the situation that can not cause front-wheel vibration in the transverse force that produces on the trailing wheel or the situation that yaw vibrates can not take place in vehicle compare, according to the steering direction that is undertaken by chaufeur (promptly, turn to according to this and to rotate or to return), in neutral direction or finish to make front-wheel steering on the direction.Thus, even the yaw vibration may take place in front-wheel vibration or the vehicle, also can place and turn to vibration and yaw to vibrate coupled to each other even the transverse force of trailing wheel may cause.This can cause the convergence of front-wheel vibration.That is the constringent convergence that improves vehicle simultaneously that can turn in raising.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device applies described steering effort to control the rudder angle of described front-wheel.

According in this respect, can realize aforementioned effect with so-called active steering mechanism (that is, being used for carrying out the steering hardware that turns to control) by the input rudder angle.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device is based on the steering effort that turns to torque to control to be applied to described front-wheel according to the steering operation of the chaufeur of described vehicle.

According in this respect, compare with situation that can the direct control rudder angle, can when turning to impression, improvement realize aforementioned effect.

(2) apply the judgement that restrains steering effort

In aspect another of Vehicular steering control apparatus of the present invention, if the described ratio of the described transverse force of the described transverse force of described trailing wheel and described front-wheel greater than predetermined first threshold values, then described steering effort bringing device applies described convergence steering effort.

According in this respect, if the ratio of the transverse force of the transverse force of trailing wheel and front-wheel greater than predetermined first threshold values, then can be judged the yaw vibration may take place in the vehicle.

Incidentally, the vibration of the yaw in the vehicle mainly often takes place after Vehicular turn.Therefore, can when Vehicular turn, carry out the judgement that the yaw vibration may take place in the vehicle.

If at the described ratio of the described transverse force of the described transverse force of aforesaid wherein described trailing wheel and described front-wheel then in applying aspect of Vehicular steering control apparatus of described convergence steering effort greater than predetermined first threshold values, if the ratio of the rudder angle of the described transverse force of described trailing wheel and described front-wheel is greater than predetermined second threshold values, then described steering effort bringing device applies described convergence steering effort.

Utilize this structure, because can estimate or calculate the transverse force of front-wheel, so the yaw vibration may take place in the vehicle if the ratio of the rudder angle of the transverse force of trailing wheel and front-wheel greater than predetermined second threshold values, then can be judged by the rudder angle of front-wheel.

In aspect another of Vehicular steering control apparatus of the present invention, if the ratio of the rudder angle of the angle of roll of described vehicle and described front-wheel greater than predetermined the 3rd threshold values, then described steering effort bringing device applies described convergence steering effort.

In the vehicle such as baby truck and SUV (SUV (sport utility vehicle)), because remained shock on the inclination direction or counteraction vibration, make the generation of the transverse force that postpones front-wheel or trailing wheel with relative tall vehicle height.So,,, can judge more suitably also whether the yaw vibration may take place in vehicle even in vehicle with relative tall vehicle height according in this respect.

(3) calculating of convergence steering effort

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each.

According in this respect, can calculate the convergence steering effort suitably.Incidentally, can be with the differential value of the transverse force of the ratio value of the transverse force of trailing wheel and trailing wheel be calculated as the convergence steering effort with value.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device is revised described convergence steering effort according to the speed of described vehicle.

According in this respect, even the rapid change of vehicle also can be stablized vehicle characteristics.Particularly, the speed rising along with vehicle can reduce to restrain steering effort.

Incidentally, can revise in the differential value of transverse force of the ratio value of trailing wheel transverse force and trailing wheel at least one according to the speed of vehicle, it is the basis when calculating the convergence steering effort.At least one the coefficient (in other words, gain) of differential value that when calculating the convergence steering effort, can be used in the case, the transverse force of the ratio value of transverse force of trailing wheel and trailing wheel according to the speed correction of vehicle.And, along with the speed rising of vehicle, further reduction ratio.In addition, the symbol of coefficient that can be used in the ratio value of transverse force when the specific speed of vehicle under neutral steering state reverses.

Wherein according in aspect of the Vehicular steering control apparatus of the speed correction of vehicle convergence steering effort, if described vehicle travels on rasping road, then described steering effort bringing device reduces described convergence steering effort aforesaid.

Utilize this structure,, then can apply the convergence steering effort to realize suitable relatively turning to even significantly change in the speed of the last vehicle of rasping road (particularly, for example rough road hangs down μ road etc.).

If on rasping road, travel then in reducing aspect of Vehicular steering control apparatus of described convergence steering effort at aforesaid wherein described vehicle, described steering effort bringing device can calculate described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, if described vehicle travels on described rasping road simultaneously, then compare, reduce the share of described differential value of the described transverse force of described trailing wheel with the situation that described vehicle travels on ordinary road.

Utilize this structure, can be by reducing because the share of the differential value of the transverse force that makes that its noise increases of travelling on rasping road is calculated the convergence steering effort.Therefore, can prevent to apply convergence steering effort excessive or that significantly change.

Incidentally, can be set at 0 ratio value by share and calculate the convergence steering effort the differential value of transverse force based on transverse force.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device calculates described convergence steering effort based on the kinematic model of described vehicle on in-plane.

According in this respect, can highly precisely calculate the convergence steering effort based on the vehicle momentum that produces by vehicle.That is, replacement can come the theoretical steering effort that calculates based on the actual motion model of vehicle only by calculating steering efforts such as synopsis.Therefore, can highly precisely calculate the convergence steering effort.

In aspect of the aforesaid Vehicular steering control apparatus that wherein calculates described convergence steering effort based on the kinematic model of described vehicle on in-plane, described steering effort bringing device based on reflected the input that turns to torque, the described kinematic model of described vehicle on described in-plane calculate described convergence steering effort.

Utilize this structure, can highly precisely calculate the convergence steering effort based on the momentum and the torque that when front-wheel turns to, produce by vehicle.

(4) collaborative with turning to of carrying out of chaufeur

In aspect another of Vehicular steering control apparatus of the present invention, if at least one in the absolute value of the absolute value of deflection angle and turning velocity is equal to or less than predetermined the 4th threshold values, then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider chaufeur in the relative small range of absolute value of the absolute value of deflection angle and/or turning velocity, easily experience turn to impression change (for example, turn to the change of torque), can prevent to turn to and experience variation by reducing to restrain steering effort (and, thereby be reduced to the limit and be set at 0) will restrain steering effort by restraining steering effort.

Incidentally, do not apply convergence steering effort (that is, will restrain steering effort and be set at 0), can apply basic steering effort, it is based on the steering effort that turns to torque according to the steering operation that is undertaken by chaufeur.Similarly, in the following explanation,, can be set at 0 and apply basic steering effort by restraining steering effort when convergence steering effort when reducing.

In aspect another of Vehicular steering control apparatus of the present invention, if at least one in the absolute value of the absolute value of deflection angle and turning velocity is equal to or greater than predetermined the 5th threshold values (wherein the 5th threshold value is greater than aforementioned the 4th threshold value), then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider exist if the absolute value of the absolute value of deflection angle and turning velocity is relatively large chaufeur carry out hedging turn to than high likelihood, can be by reducing to restrain the deterioration that steering effort prevents the hedging performance.

In aspect another of Vehicular steering control apparatus of the present invention, if the steering direction that the chaufeur of described vehicle carries out is opposite with the direction that applies described steering effort, then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider exist chaufeur to carry out to evade if steering direction is opposite with the direction that applies steering effort accident turn to than high likelihood, can be by reducing to restrain steering effort or being set at 0 deterioration that prevents to evade performance by restraining steering effort.

In aspect another of Vehicular steering control apparatus of the present invention, if the steering direction that the chaufeur of described vehicle carries out is opposite with the direction that applies described steering effort, then described steering effort bringing device applies described steering effort to described trailing wheel.

According in this respect, can prevent that turning to of chaufeur experience variation by making rear-axle steering.In the case, can apply basic steering effort to trailing wheel.

If it is opposite with the direction that applies described steering effort then in described trailing wheel applies aspect of Vehicular steering control apparatus of described convergence steering effort at steering direction that the chaufeur of aforesaid wherein described vehicle carries out, turning under the situation of vibration, even the described steering direction that the described chaufeur of described vehicle carries out is opposite with the described direction that applies described steering effort, described steering effort bringing device still applies described convergence steering effort.

Utilize this structure, when taking place maybe to turn to vibration, can evade performance, lay particular emphasis on the stability (that is, preventing the generation of yaw vibration) of vehicle more by applying the convergence steering effort, comparing.

(5) foe and aft force control

In aspect another of Vehicular steering control apparatus of the present invention, if described vehicle is changed the foe and aft force control of the foe and aft force of described vehicle, then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider and carrying out foe and aft force control (particularly, for example ABS (anti-skid brake system) control, VSC (vehicle stability control), TRC (traction control)) situation under the transverse force change or by making front-wheel steering not necessarily obtain predetermined lateral power easily of trailing wheel, reduce to restrain steering effort.

In addition, except actual situation of carrying out foe and aft force control, even under the situation that has the control of beginning foe and aft force, also can reduce to restrain steering effort than high likelihood.

If then in reducing aspect of described Vehicular steering control apparatus of described convergence steering effort in the foe and aft force control of the aforesaid foe and aft force that wherein described vehicle is changed described vehicle, if described vehicle is not carried out described foe and aft force control, then described steering effort bringing device can calculate described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, and described steering effort application devices can calculate described convergence steering effort based in the described differential value of the described transverse force of the described ratio value of the described transverse force of described trailing wheel and described trailing wheel each, if simultaneously described vehicle is carried out described foe and aft force control, then compare, reduce the share of described ratio value of the described transverse force of described trailing wheel with the situation of not carrying out the control of described foe and aft force.

Utilize this structure, the share of ratio value (it can significantly change owing to foe and aft force control) that can be by reducing transverse force (in other words, the share of the differential value by increasing transverse force (even itself because change of the speed of vehicle also can significantly not change)), calculate the convergence steering effort.Therefore, can prevent to apply convergence steering effort excessive or that significantly change.

Incidentally, can be set at 0 differential value by share and calculate the convergence steering effort the ratio value of transverse force based on transverse force.Similarly, in the following explanation, when the share of the ratio value of transverse force reduces, can be set at 0 differential value by share and calculate the convergence steering effort the ratio value of transverse force based on transverse force.

If wherein carry out foe and aft force control then in calculating aspect of described Vehicular steering control apparatus of described convergence steering effort when reducing the described share of described ratio value of described trailing wheel aforesaid, if carry out the described foe and aft force control of the described foe and aft force that changes described vehicle, then described steering effort bringing device does not apply described convergence steering effort, and described steering effort bringing device at first applies the described convergence steering effort that the described differential value based on the described transverse force of described trailing wheel calculates during the scheduled time slot after the control of described foe and aft force finishes, and applies the described convergence steering effort that the described share of the described ratio value of the described transverse force by increasing described trailing wheel in time gradually calculates then.

Utilize this structure, even if the ratio value of transverse force also significantly changes after finishing foe and aft force control, then at first calculate the convergence steering effort based on the differential value of transverse force, under the situation that the change according to the ratio value of transverse force reduces gradually along with effluxion, in the share of scaling up value, calculate the convergence steering effort then based on ratio value and differential value.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, reduces the described share of described ratio value of the described transverse force of described trailing wheel simultaneously more along with the increase of the acceleration/accel of described vehicle or deceleration/decel.

According in this respect, the share of ratio value that can be by reducing transverse force (it can significantly change owing to bigger acceleration/accel or deceleration/decel) (in other words, the share of the differential value by increasing transverse force (even itself because change of the speed of vehicle also can significantly not change)), calculate the convergence steering effort.Therefore, can prevent to apply convergence steering effort excessive or that significantly change.

Incidentally, in when, owing to bigger acceleration/accel or deceleration/decel trim taking place, compare with the situation that trim does not take place, can be in the share of the ratio value of the transverse force that reduces trailing wheel, calculate the convergence steering effort based in the differential value of the transverse force of the ratio value of the transverse force of trailing wheel and trailing wheel each.

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, simultaneously in the scheduled time slot after the acceleration/accel of described vehicle or deceleration/decel begin to change, keep stable situation to compare with described acceleration/accel and deceleration/decel, reduce the share of described ratio value of the described transverse force of described trailing wheel.

In the scheduled time slot after acceleration/accel or deceleration/decel begin to change (in other words, in the period before the trim convergence of the vehicle that is caused by acceleration/accel or deceleration/decel), the ratio value of transverse force can significantly change.Therefore, according in this respect, can calculate the convergence steering effort by the share that reduces ratio value.So, can prevent to apply excessively or the convergence steering effort that significantly changes.Promptly, in when, owing to bigger acceleration/accel or deceleration/decel inclination taking place, compare with the situation that trim does not take place, can be in the share of the ratio value of the transverse force that reduces trailing wheel, calculate the convergence steering effort based in the differential value of the transverse force of the ratio value of the transverse force of trailing wheel and trailing wheel each.

(6) vertically load

In aspect another of Vehicular steering control apparatus of the present invention, if change the load control of the vertical load of described front-wheel, then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider if the control of loading (particularly, for example suspension control, stabiliser control etc.) then the transverse force of trailing wheel change easily or, reduce to restrain steering effort by making front-wheel steering not necessarily obtain the transverse force of expecting.

In addition, except the situation of the actual control of loading, even under existence begins to load the situation of controlling than high likelihood, also can reduce to restrain steering effort.Can also reduce to restrain steering effort along with the increase of the change of per unit load.In addition, as the situation of carrying out foe and aft force control, compare with the situation of the control of not loading, can be under the situation of the share of the ratio value of the transverse force that reduces trailing wheel, calculate the convergence steering effort based on the differential value of the transverse force of the ratio value of the transverse force of trailing wheel and trailing wheel.

(7) be involved in

In aspect another of Vehicular steering control apparatus of the present invention, if exist in be involved in the described vehicle may or if described being involved in have been taken place, then described steering effort bringing device reduces described convergence steering effort.

According in this respect, consider owing to be involved in and make the transverse force of trailing wheel change easily or the transverse force that not necessarily obtains expectation that turns to by front-wheel, reduce to restrain steering effort.

Incidentally, if if exist be involved in may or take place to be involved in, then can apply the steering effort that can make front-wheel steering, to guarantee stablizing of vehicle along the direction of the rotation of evading vehicle.

(8) the vibration performance value of front-wheel

In aspect another of Vehicular steering control apparatus of the present invention, described steering effort bringing device involving vibrations eigenwert modifier, it is used for may causing in the described transverse force of described trailing wheel the vibration performance value of the described front-wheel of change under the vibrative situation of described front-wheel.

According in this respect, even, also can prevent to turn to vibration and yaw vibration coupled to each other by the vibration performance value that changes front-wheel even may cause front-wheel to produce vibration or yaw may take place in vehicle vibrating in the transverse force that produces on the trailing wheel.The person can cause the convergence of the vibration of front-wheel.That is the constringent convergence that improves vehicle simultaneously that can turn in raising.

In the aforesaid Vehicular steering control apparatus that is provided with vibration performance value modifier, each of described front-wheel that described vibration performance value modifier can make the described front-wheel that is positioned at the right side and be positioned at the left side turns to different rudder angles respectively, if and the described transverse force of described trailing wheel may cause described front-wheel to produce vibration, then described vibration performance value modifier applies and is used to make the steering effort of described front-wheel to prenex directional steering.

Utilize this structure, change turning power (comerpower) to prenex directional steering by making front-wheel.Therefore, can change the vibration performance value of front-wheel.

According to the embodiment of following explanation, these effects of the present invention and advantage will become clearer.

Description of drawings

Fig. 1 is the Probability Structure view of basic structure that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.

Fig. 2 is the diagram of circuit that the integrated operation of electric power steering apparatus conceptually is shown.

Fig. 3 is illustrated in the diagram of circuit that calculates the calculating operation of target diversion torque among the step S200 of Fig. 2.

Fig. 4 is conceptually illustrated in the diagram of circuit of judging the decision operation of overshoot state among the step S210 of Fig. 3.

Fig. 5 is the diagram of circuit that is conceptually illustrated in reverse auxiliary judgment operation among the step S220 of Fig. 3.

Fig. 6 is the figure that deflection angle and turning velocity are shown.

Fig. 7 conceptually illustrates to calculate the diagram of circuit that the basis turns to the calculating operation of torque among the step S230 of Fig. 3.

Fig. 8 illustrates to turn to torque and basis to turn to the figure that concerns between the torque.

Fig. 9 conceptually illustrates to calculate the diagram of circuit that convergence turns to the calculating operation of torque among the step S240 of Fig. 3.

Figure 10 illustrates based on the coefficient of the speed of a motor vehicle and the figure of the relation between the speed of a motor vehicle.

Figure 11 illustrates based on the coefficient of the speed of a motor vehicle and the figure of the relation between the speed of a motor vehicle.

Figure 12 is the figure of the value of acceleration factor before and after illustrating with respect to the absolute value of front and back acceleration/accel.

Figure 13 is the value of acceleration factor before and after illustrating begins elapsed time with respect to acceleration/accel before and after change figure.

Figure 14 illustrates the figure of ABS coefficient with respect to the time.

Figure 15 is the summary construction diagram of basic structure of first modified example that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.

Figure 16 is the summary construction diagram of basic structure of second modified example that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.

Description of reference numerals

1 vehicle

5,6 front-wheels

7,8 trailing wheels

10 electric power steering apparatus

11 steering handwheels

13 steering angle sensors

14 torque sensors

15,55 electrical motors

30ECU

31 angle of roll computing circuits

32 are involved in decision circuitry

The 33ABS control circuit

34SUS (suspension) control circuit

41 car speed sensors

42 transverse force sensor

61,62 active steering actuators

The specific embodiment

After this, will be with reference to the accompanying drawings, explain with each embodiment in order to be used to realize preferred forms of the present invention.

(1) basic structure

At first, with reference to figure 1, will give an explaination to the basic structure of the embodiment of Vehicular steering control apparatus of the present invention.Fig. 1 is the summary construction diagram of basic structure that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.

As shown in Figure 1, vehicle 1 is provided with front- wheel 5 and 6 and trailing wheel 7 and 8.Any one propulsive effort by the acquisition driving engine at least in front-wheel and the trailing wheel is driven.Simultaneously, front-wheel is diverted, and makes vehicle 1 to travel along desired orientation.

Front- wheel 5 and 6 as wheel flutter is turned to by electric power steering apparatus 10, and electric power steering apparatus 10 is according to being driven by the manipulation of chaufeur to steering handwheel 11.Particularly, electric power steering apparatus 10 is rack pinion electric power steering apparatus for example, and it is provided with: steering shaft 12, and the one end is connected to steering handwheel 11; Rack and pinion mechanism 16, it is connected to the other end of steering shaft 12; Steering angle sensor 13, it is used to detect the deflection angle θ as the corner of steering handwheel 11; Torque sensor 14, it is used to detect by what handle that steering handwheel 11 is applied to steering shaft 12 and turns to torque M T; And electrical motor 15, it is used to produce the assisted diversion power that turns to burden that reduces chaufeur and is used for by for graphic reducing gear assisted diversion power being applied to steering shaft 12.

In electric power steering apparatus 10, ECU 30 based on from the deflection angle θ of steering angle sensor 13 output, from the angle of roll RA of the vehicle 1 of angle of roll computing circuit 31 outputs, from be involved in control signal S1 that whether decision circuitry 32 outputs and expression are involved in, from the output of ABS control circuit and expression whether carry out ABS control control signal S2, from 34 outputs of suspension (SUS) control circuit and expression whether carry out the control signal S3 of stabiliser control or suspension control, from the vehicle velocity V of car speed sensor 41 outputs and from the transverse force F of the front-wheel of transverse force sensor 42 outputs _fTransverse force F with trailing wheel _rCalculate target diversion torque T, target diversion torque T is the torque for the treatment of by electrical motor 15 generations.

In the case, angle of roll computing circuit 31 comes calculation side inclination angle tire air RA based on the transverse gravity G that is detected by horizontal G sensor 43.Be involved in decision circuitry 32 based on producing the control signal S1 whether expression is involved in by the yaw rate gamma of yaw rate sensor pivot 44 detections and the throttle opening O that detects by engine load sensor 45.

Target diversion torque T outputs to electrical motor 15 from ECU 30, and based target turns to the electric current of torque T to be fed to electrical motor 15, by this current drives electrical motor 15.Thus, turn to auxiliary force to be applied to steering shaft 12 from electrical motor 15, it causes chaufeur to turn to alleviating of burden.And, utilize rack and pinion mechanism 16, the power on the hand of rotation of steering shaft 12 is converted to the power of the reciprocating direction of tooth bar 17.The two ends of tooth bar 17 are connected to front- wheel 5 and 6 by connecting rod 18 respectively, and the direction of front- wheel 5 and 6 changes along with the crank motion of tooth bar 17.

Incidentally, transverse force sensor 42 can directly detect transverse force F _fAnd F _rPerhaps, for example, transverse force sensor 42 is not set, ECU 30 can be by computing and calculating etc. based on other parameter estimation (in other words, calculating) transverse force F _fAnd F _rSimilarly, in other various sensors, can be by the directly detection target of detecting sensor of sensor be set.Perhaps, sensor for example is not set, ECU 30 can be by the detection target based on other parameter estimation sensors such as computing and calculating.

(2) operating principle

Then, referring to figs. 2 to Figure 14, will provide more detailed explanation to the operation of the electric power steering apparatus in the present embodiment 10.

Fig. 2 is the diagram of circuit that the overall work of electric power steering apparatus 10 conceptually is shown.As shown in Figure 2, if igniting is ON (step S100: "Yes"), then drive electric power steering apparatus 10.Particularly, calculate target torque T (step S200), and turn to torque control (step S300) by carrying out according to the target torque T driving motor 15 that calculates by the operation of ECU 30.

Fig. 3 is the diagram of circuit that is illustrated in the calculating operation that calculates target diversion torque T among the step S200 of Fig. 2.As shown in Figure 3, if calculate target torque T, at first the step S210 at Fig. 3 judges the overshoot state that whether is in that turns to.As shown in Figure 4, in order to judge the overshoot state that whether is in that turns to, the ratio of at first judging the rudder angle δ of the transverse force Fr of trailing wheel 7 and 8 and front- wheel 5 and 6 is not more than predetermined threshold OS1, and (step S211: "No"), whether the ratio of rudder angle δ of then judging angle of roll RA and front- wheel 5 and 6 is greater than predetermined threshold OS2 (step S212).

As the judged result of step S212, if the ratio of rudder angle δ that is judged as angle of roll RA and front- wheel 5 and 6 is greater than predetermined threshold OS2 (step S212: "Yes"), then be judged as the overshoot state (step S214) that is in that turns to.Therefore, convergence being turned to torque calculation is target diversion torque T.

On the other hand, judged result as step S212, be not more than predetermined threshold OS2 (step S212: "No"), then be judged as the overshoot state that is not in (that is it is stable, turning to) (step S213) that turns to if be judged as the ratio of the rudder angle δ of angle of roll RA and front-wheel 5 and 6.Therefore, the basis being turned to torque calculation is target diversion torque T.

Incidentally, be additional to or the judgement of alternative steps S211, can judge the transverse force F of trailing wheel 7 and 9 _rTransverse force F with front- wheel 5 and 6 _fRatio whether greater than predetermined threshold OS3.If be judged as the transverse force F of trailing wheel 7 and 8 _rTransverse force F with front- wheel 5 and 6 _fRatio greater than predetermined threshold OS3, then be judged as the overshoot state that is in that turns to.If be judged as the transverse force F of trailing wheel 7 and 8 _rTransverse force F with front- wheel 5 and 6 _fRatio be not more than predetermined threshold OS3, the then judgement of execution in step S212.

In addition, based on the rudder angle δ of front- wheel 5 and 6 and the transverse force F of trailing wheel 7 and 8 _rBetween hysteresis loop, front- wheel 5 and 6 the rudder angle δ and the transverse force F of the hysteresis loop between the angle of roll RA and trailing wheel 7 and 9 _rTransverse force F with front- wheel 5 and 6 _fBetween hysteresis loop (particularly, hysteresis loop under the relatively low situation of the speed of a motor vehicle, and the hysteresis loop under the relative condition with higher of the speed of a motor vehicle), under the situation of the various features of considering vehicle 1 grade, each preferred value that all preferably is set at experiment, experience, arithmetic, theory or uses simulation etc. with threshold value OS1, OS2 and OS3 for each vehicle 1 that is equipped with electric power steering apparatus 10.But establishing method is unrestricted, as long as it can preferably judge the overshoot state that whether is in that turns to by using threshold value.

Fig. 5 is the diagram of circuit that the reverse auxiliary judgment operation among the step S220 of Fig. 3 conceptually is shown.Shown in figure front-wheel 5, in order to judge whether that carrying out you wants to assist, the direction opposite (step S221) whether the steering direction of at first judging the steering handwheel 11 that is undertaken by chaufeur turns to front- wheel 5 and 6 with the steering effort that is applied by electrical motor 15.

As the judged result of step S221, if be judged as opposite (the step S221: "Yes"), then judge the transverse force F of trailing wheel 7 and 8 of the steering direction of the steering handwheel 11 that is undertaken by chaufeur with the direction that the steering effort that is applied by electrical motor 15 turns to front- wheel 5 and 6 _rWith the ratio of the rudder angle δ of front- wheel 5 and 6 whether greater than predetermined threshold OS4 (step S225).Particularly, judge whether to turn to vibration.Therefore, threshold value OS4 is greater than threshold value OS1.In addition, though threshold value OS4, also based on the rudder angle δ of front- wheel 5 and 6 and the transverse force F of trailing wheel 7 and 8 _rBetween hysteresis loop (hysteresisloop), under the situation of the various features of considering vehicle 1 grade, it preferably is set at the preferred value of experiment, experience, arithmetic, theory or use simulation etc. for each vehicle 1 that is equipped with electric power steering apparatus 10.But establishing method is unrestricted, as long as it can preferably judge whether to turn to vibration by using threshold value.

As the judged result of step S225, if be judged as the transverse force F of trailing wheel 7 and 8 _rWith the ratio of the rudder angle δ of front- wheel 5 and 6 greater than predetermined threshold OS4 (step S225: "Yes"), then be judged as and be not reverse auxiliary (step S226).Therefore, convergence being turned to torque calculation is target diversion torque T.

On the other hand, as the judged result of step S225, if be judged as the transverse force F of trailing wheel 7 and 8 _rBe not more than predetermined threshold OS4 (step S225: "No"), then be judged as reverse auxiliary (step S227) with the ratio of the rudder angle δ of front-wheel 5 and 6.Therefore, the basis being turned to torque calculation is target diversion torque T.

On the other hand, judged result as step S221, if be judged as not opposite (the step S221: "No") of the steering direction of the steering handwheel 11 that is undertaken by chaufeur with the direction that the steering effort that is applied by electrical motor 15 turns to front- wheel 5 and 6, whether the absolute value of deflection angle θ of then judging steering handwheel is less than predetermined value OS5_1, and whether the absolute value of the turning velocity (that is deflection angle speed d θ) of judgement steering handwheel 11 is less than predetermined value OS5_2 (step S222).

Judged result as step S222, if the absolute value of deflection angle θ that is judged as steering handwheel 11 is less than predetermined value OS5_1, and the absolute value of turning velocity d θ that is judged as steering handwheel 11 is less than predetermined value OS5_2 (step S222: "Yes"), then be judged as reverse auxiliary (step S227).Therefore, the basis being turned to torque calculation is target diversion torque T.

Incidentally, if the absolute value of the turning velocity d θ of steering handwheel 11 less than predetermined value OS5_2, even the absolute value of the deflection angle θ of steering handwheel 11 is not less than predetermined value OS5_1, also can be judged as reverse auxiliary.In addition, if the absolute value of the deflection angle θ of steering handwheel 11 less than predetermined value OS5_1, even the absolute value of the turning velocity d θ of steering handwheel 11 is not less than predetermined value OS5_2, also can be judged as reverse auxiliary.

On the other hand, judged result as step S221, be not less than predetermined value OS5_1 if be judged as the absolute value of the deflection angle θ of steering handwheel 11, the absolute value that perhaps is judged as the turning velocity d θ of steering handwheel 11 is not less than predetermined value OS5_2 (step S22: "No"), whether the absolute value of deflection angle θ of then judging steering handwheel 11 greater than predetermined value OS6_1, and whether the absolute value of turning velocity d θ of judging steering handwheel 11 is greater than predetermined value OS6_2 (step S223).

Judged result as step S223, if the absolute value of deflection angle θ that is judged as steering handwheel 11 is greater than predetermined value OS6_1, and the absolute value of turning velocity d θ that is judged as steering handwheel 11 is greater than predetermined value OS6_2 (step S223: "Yes"), then be judged as reverse auxiliary (step S227).Therefore, the basis being turned to torque calculation is target diversion torque T.

Incidentally, if the absolute value of turning velocity d θ that is judged as steering handwheel 11 is not more than predetermined value OS6_1 greater than predetermined value OS6_2 even be judged as the absolute value of the deflection angle θ of steering handwheel 11, also can be judged as reverse auxiliary.In addition, if the absolute value of deflection angle θ that is judged as steering handwheel 11 is not more than predetermined value OS6_2 greater than predetermined value OS6_1 even be judged as the absolute value of the turning velocity d θ of steering handwheel 11, also can be judged as reverse auxiliary.

On the other hand, judged result as step S223, be not more than predetermined value OS6_1 if be judged as the absolute value of the deflection angle θ of steering handwheel 11, perhaps the absolute value of the turning velocity d θ of steering handwheel 11 is not more than predetermined value OS6_2 (step S223: "No"), judge then whether vehicle 1 is in the state of being involved in (perhaps existing vehicle 1 to be in the possibility of the state of being involved in) (step S224).Based on carrying out this judgement from the control signal S1 that is involved in decision circuitry 32 outputs.

As the judged result of step S224, be in the state of being involved in (perhaps existing vehicle 1 to be in the possibility of the state of being involved in) (step S224: "Yes"), then be judged as reverse auxiliary (step S227) if be judged as vehicle 1.Therefore, the basis being turned to torque calculation is target diversion torque T.

On the other hand, as the judged result of step S224, be not in the state of being involved in (perhaps not existing vehicle 1 to be in the possibility of the state of being involved in) (step S224: "No"), then be judged as and be not reverse auxiliary (step S226) if be judged as vehicle 1.Therefore, convergence being turned to torque calculation is target diversion torque T.

Here, figure as shown in Figure 6 is shown the operation table of step S222 and step S223 in the figure of deflection angle θ and turning velocity d θ.In the figure of Fig. 6,, then be judged as and be not reverse auxiliary if the combination of deflection angle θ and turning velocity d θ is in the shadow region.If deflection angle θ and turning velocity d θ are combined in outside the shadow region, then be judged as reverse auxiliary.

Incidentally, even threshold value OS5_1, OS5_2, OS6_1 and OS6_2, also under the situation of the various features of considering vehicle 1 grade, it preferably is set at the preferred value of experiment, experience, arithmetic, theory or use simulation etc. for each vehicle 1 that is equipped with electric power steering apparatus 10.

Fig. 7 conceptually illustrates to calculate the diagram of circuit that the basis turns to the calculating operation of torque among the step S230 of Fig. 3.As shown in Figure 7, turn to torque, at first be read as and calculate the basic required various signals (step S231) of torque that turn in order to calculate the basis.Then, calculate the basis based on the various signals that read at step S231 and turn to torque (step S232).

Particularly, turn to torque M T and basis to turn to the figure that concerns between the torque to calculate the basis based on as shown in Figure 8 expression and turn to torque.In order to ensure the surplus (slackness (looseness)) of steering handwheel 11, if turn to torque M T less relatively then the basis is turned to torque calculation is 0.If turn to the size of torque M T to have certain level, the basis that then calculates turns to torque to increase along with the increase that turns to torque M T.If turn to torque M T greater than predetermined value, the basis that then calculates turns to torque not change along with the size that turns to torque M T, and becomes fixed value.At this moment, the basis turns to torque and to reduce along with the vehicle velocity V rising.

Fig. 9 conceptually illustrates to calculate the diagram of circuit that convergence turns to the calculating operation of torque among the step S240 of Fig. 3.As shown in Figure 9, when the calculating convergence turns to torque, at first set COEFFICIENT K based on the speed of a motor vehicle _V1And K _V2(step S241).

Particularly, according to as shown in figure 10 expression COEFFICIENT K based on the speed of a motor vehicle _V1And the figure of the relation between the vehicle velocity V sets the COEFFICIENT K based on the speed of a motor vehicle _V1Basis expression as shown in figure 11 is based on the COEFFICIENT K of the speed of a motor vehicle in the same manner _V2And the figure of the relation between the vehicle velocity V sets the COEFFICIENT K based on the speed of a motor vehicle _V2

Can obtain COEFFICIENT K as shown in Figure 10 and Figure 11 by the equation of motion of the motion of expression vehicle 1 on in-plane based on the speed of a motor vehicle _V1And K _V2Particularly, the equation of motion of vehicle 1 is by equation 1 to 4 expression, and wherein the moment of inertia of vehicle 1 is I, and the front axle and the distance between the center-of-gravity position of vehicle 1 are L _f, the rear axle and the distance between the center of gravity of vehicle 1 are L _r, dragging the amount of drawing (trailamount) is L _t, the slip angle of vehicle 1 is β, the turning power on the front-wheel is K _f

[equation 1]

$I\stackrel{\·}{\mathrm{\γ}}=F_f{L}_f-F_r{L}_r$

[equation 2]

$\mathrm{mV}(\stackrel{\·}{\mathrm{\β}}+\mathrm{\γ})=F_f+F_r$

[equation 3]

$F_f=2K_f(\mathrm{\δ}-\mathrm{\β}-\frac{L_f}{V}\mathrm{\γ})$

[equation 4]

$F_r=2K_r(-\mathrm{\β}+\frac{L_r}{V}\mathrm{\γ})$

In addition, heavy at present embodiment, electric power steering apparatus 10 adopts the torque input method.Therefore, be suitable for following equation front-wheel 5, wherein front- wheel 5 and 6 moment of inertia are I _h, coefficient of viscosity is C _h, turning to torque is T _h

[equation 5]

If (in other words at the yaw vibration that suppresses vehicle 1, increase the damping of vehicle 1) obtain target torque T (promptly by using equation 1 to 5, if the equation that obtains by the right side that target torque T is applied to equation front-wheel 5 is solved an equation), then becoming need be based on the transverse force F of trailing wheel 7 and 8 _rWith transverse force F _rDifferential value come target setting to turn to torque T (convergence turn to torque) in the case.Particularly, become and target diversion torque T need be set at by the transverse force F with trailing wheel 7 and 8 _rMultiply by value that particular factor A obtains and by transverse force F with trailing wheel 7 and 8 _rDifferential value dF _rMultiply by value that particular factor B obtains and value.Coefficient A and B correspond respectively to the COEFFICIENT K based on the speed of a motor vehicle _V1And K _V2

As shown in Figure 10 and Figure 11, the COEFFICIENT K that obtains in the above described manner based on the speed of a motor vehicle _V1And K _V2Each all changes along with vehicle velocity V.

Particularly, based on the COEFFICIENT K of the speed of a motor vehicle _V1Symbol reverse at (particularly, under neutral steering state) under the situation of the specific speed of a motor vehicle.Particularly, based on the COEFFICIENT K of the speed of a motor vehicle _V1Below the specific speed of a motor vehicle, have on the occasion of, based on the COEFFICIENT K of the speed of a motor vehicle _V1More than the specific speed of a motor vehicle, has negative value.This expression consider since vehicle surpass under the situation of specific speed the easy oversteer of behavior and for fear of oversteer, along the directional steering opposite (in other words with the chaufeur steering direction, make chaufeur be difficult to rotate steering handwheel) time, target setting turns to torque.That is, expression is set at the behavior of stablizing vehicle 1 with target diversion torque T.

As mentioned above, can be based on K _V1* F _r+ K _V2* dF _rThe equation convergence of calculating as target diversion torque T turn to torque.But on the contrary, according to the behavior of vehicle 1 etc., the application of aforementioned convergence turns to torque with behavior that may deterioration vehicle 1.Therefore, in the present embodiment, calculate convergence by operation below the further execution and turn to torque.

Particularly, in Fig. 9, at first set the rasping road COEFFICIENT K _B(step S242).With the rasping road COEFFICIENT K _BBe set at the numerical value in the scope between 0 and 1.If vehicle 1 travels on rasping road (for example, vehicle velocity V road significantly irregular or that undesirably do not change for example hangs down μ road and rough road thereon), then with the rasping road COEFFICIENT K _BBe set at 0.Perhaps, if vehicle 1 travels on rasping road, then can be with the rasping road COEFFICIENT K _BBe set at greater than 0 and less than 1 value.On the other hand, if vehicle 1 does not travel on rasping road (that is), then with the rasping road COEFFICIENT K if vehicle 1 travels on the ordinary road such as paving road _BBe set at 1.

Then, set front and back acceleration factor K _A(step S243).With front and back acceleration factor K _ABe set at the numerical value in the scope between 0 and 1.

Particularly, set according to as shown in figure 12 figure before and after acceleration factor K _AFigure 12 is acceleration factor K before and after illustrating _AValue with respect to the figure of the absolute value of front and back acceleration alpha.As shown in figure 12, if the absolute value of the front and back acceleration alpha of vehicle 1 is equal to or less than predetermined value, then with front and back acceleration factor K _ABe set at 1.If the absolute value of the front and back acceleration alpha of vehicle 1 is equal to or greater than predetermined value, then along with the increase of the absolute value of the front and back acceleration alpha of vehicle 1 and with front and back acceleration factor K _ABe set at littler.Perhaps, if the absolute value of the front and back acceleration alpha of vehicle 1 is equal to or greater than in predetermined value or the vehicle 1 trim takes place, then can be with front and back acceleration factor K _ABe set at 0.

In addition, as shown in figure 13, can begin elapsed time according to acceleration alpha before and after change and set front and back acceleration factor K _AFigure 13 is acceleration factor K before and after illustrating _AValue begin the figure of elapsed time with respect to acceleration alpha before and after change.As shown in figure 13, if the front and back acceleration alpha begins to change, can be with front and back acceleration factor K _ABe set at 0, up to for the specific corresponding effluxion of trim cycle of vehicle 1.Can be with front and back acceleration factor K _ABe set at corresponding effluxion of trim cycle after time durations have big value gradually.

In Fig. 9, after this set the ABS COEFFICIENT K _X1And K _X2(step S244).With the ABS COEFFICIENT K _X1And K _X2Be set at the numerical value in the scope between 0 and 1.

Particularly, set the ABS COEFFICIENT K according to as shown in figure 14 figure _X1And K _X2Figure 14 illustrates the ABS COEFFICIENT K _X1And K _X2Value with respect to the figure of time.Can judge whether to carry out ABS control according to control signal S2 from 33 outputs of ABS control circuit.After this, if ABS control finishes, then at first with the ABS COEFFICIENT K _X2Be set at and have the value bigger along with effluxion.Finishing through after the specified time, then with the ABS COEFFICIENT K from ABS control _X1Be set at and have the value bigger along with effluxion.At this moment, ABS COEFFICIENT K _X2The time per unit increment greater than the ABS COEFFICIENT K _X1The time per unit increment.In other words, as shown in figure 14, with the ABS COEFFICIENT K _X1Slope ratio and the ABS COEFFICIENT K of relevant figure _X2The slope of relevant figure relaxes.

Incidentally, substitute ABS control and finish to increase gradually afterwards the ABS COEFFICIENT K _X1With the ABS COEFFICIENT K _X2Operation, the specific period after ABS control finishes, can be with the ABS COEFFICIENT K _X1Being set at 1 also can be with the ABS COEFFICIENT K _X2Be set at 0, and can be then with the ABS COEFFICIENT K after specific period process _X1Continue to be set at 1.

In addition, even under the situation of carrying out foe and aft force control (for example VSC and TRC), can preferably set the ABS COEFFICIENT K with the aspect identical with ABS control _X1And K _X2

In Fig. 9, then set suspension (or SUS) COEFFICIENT K _ZWith the SUS COEFFICIENT K _ZBe set at the numerical value in the scope between 0 and 1.Particularly, if do not carry out suspension control, then with the SUS COEFFICIENT K _ZBe set at 1.Can judge whether to carry out suspension control according to control signal S3 from 34 outputs of SUS control circuit.On the other hand, if carry out suspension control, then with the SUS COEFFICIENT K _ZBe set at 0 or greater than 0 and less than 1 value.

In addition, even under the situation of carrying out vertically load control (for example stabiliser control), the SUS COEFFICIENT K is set in also preferably identical with suspension control aspect _Z

Incidentally, if vehicle velocity V unusual (for example, skidding etc. taking place), preferably will be based on the COEFFICIENT K of the speed of a motor vehicle _V1Be set at 0.

After this, calculate the transverse force F of trailing wheel 7 and 8 _rThe COEFFICIENT K of institute's actual multiplication ₁(step S246).Particularly, K ₁=K _V1* K _B* K _A* K _X1* K _ZCalculate the transverse force F of trailing wheel 7 and 8 in the same manner _rDifferential value dF _rThe COEFFICIENT K of institute's actual multiplication ₂(step S247).Particularly, K ₂=K _V2* K _X2After this, calculate the transverse force F of trailing wheel 7 and 8 _rAnd the transverse force F of trailing wheel 7 and 8 _rDifferential value dF _r(step S248).After this, the K that calculates based on step S246 ₁, the K that calculates of step S247 ₂, and the dF that calculates of step S248 _rAnd F _rCalculate convergence and turn to torque (step S249).

Here, if the steering direction that steering handwheel 11 is carried out by chaufeur is to rotate or the incision direction, then with turn to be judged as be not in the overshoot state situation (promptly, be judged as the situation of "No" at the step S210 of Fig. 3) compare, preferably apply the auxiliary force that turns to that turns to torque according to the convergence that calculates, make front- wheel 5 and 6 turn to along middle force direction from electrical motor 15.On the other hand, if the steering direction that chaufeur carries out steering handwheel 11 is to return or reverse directions, then be judged as the situation that is not in the overshoot state and compare with turning to, preferably apply the auxiliary force that turns to that turns to torque according to the convergence that calculates, make front- wheel 5 and 6 along finishing directional steering from electrical motor 15.

As mentioned above, according to present embodiment, can preferably judge the overshoot state that whether is in that turns to.Then, if turn to the overshoot state that is in, then convergence can be turned to torque settings is target diversion torque T.Thus, even turn to the overshoot state that is in, also can place the yaw vibration (particularly, preventing that both from resonating with phases opposite) coupled to each other that turns to vibration and vehicle.This can cause the convergence of the vibration of front-wheel 5 and 6.That is the constringent convergence that improves vehicle 1 simultaneously that can turn in raising.

In addition,, turn to torque, so highly precisely (or more optimally) calculating convergence turns to torque and calculate convergence based on the equation of motion on the in-plane of vehicle 1 because consider the contribution that brings by the torque input.

In addition, the rudder angle δ by monitoring front- wheel 5 and 6, front- wheel 5 and 6 transverse force F _f, trailing wheel 7 and 8 transverse force F _r, inclination square RA etc., can be preferably or highly precisely judge the overshoot state that whether is in that turns to.

Particularly, because shown in the step S212 among Fig. 4, monitor the ratio of the rudder angle δ of angle of roll RA and front- wheel 5 and 6, even in the vehicle with tall vehicle height 1 such as baby truck and SUV (SUV (sport utility vehicle)), also can be preferably or highly precisely judge the overshoot state that whether is in that turns to.Consider such advantage, can be configured to the operation of the step S212 in the execution graph 4 on vehicle selectively with tall vehicle height, and the not operation of the step S212 in the execution graph 4 on the vehicle with low height of car such as sports model car and Single-row seat automobile.

In addition, consider shown in the step S221 among Fig. 5, if the steering direction that is undertaken by chaufeur is opposite with the direction that the steering effort that is applied by electrical motor 15 turns to front- wheel 5 and 6, then chaufeur is very likely carried out urgent danger prevention, then can prevent by being set at the deterioration that target diversion torque T prevents the hedging performance according to the basic steering effort that chaufeur turns to.That is, can respect the wish of the urgent danger prevention of chaufeur.

But, even the steering direction that is undertaken by chaufeur is opposite with the direction that the steering effort that is applied by electrical motor 15 turns to front- wheel 5 and 6, if shown in the step S225 among Fig. 5, take place maybe may to turn to vibration, can be that target diversion torque T compares and turns to impression more to focus on the stable of vehicle 1 then by convergence being turned to torque settings.

Incidentally, if the steering direction that is undertaken by chaufeur is opposite with the direction that the steering effort that is applied by electrical motor 15 turns to front- wheel 5 and 6, then can also reduce the transverse force F of trailing wheel 7 and 8 _rThe COEFFICIENT K of institute's actual multiplication ₁, this COEFFICIENT K ₁It is the basis of setting with respect to the steering effort on the steering direction opposite sense that is undertaken by chaufeur.In addition, can also reduce calculating convergence trailing wheel 7 and transverse force F of 8 when turning to torque _rThe share of ratio value.

In addition, consider that in the relative small range of absolute value of the absolute value of deflection angle θ and turning velocity d θ chaufeur feels the change that turns to impression easily, shown in the step S222 among Fig. 5, to turn to torque settings according to the basis that turns to torque M T is target diversion torque T, thereby to avoid turning to of chaufeur to experience variation.

In addition, consider that chaufeur may be carried out urgent danger prevention in the relative small range of absolute value of the absolute value of deflection angle θ and turning velocity d θ, shown in the step S223 among Fig. 5, can be target diversion torque T by turning to torque settings, to respect the urgent danger prevention wish of chaufeur according to the basis that turns to torque M T.

In addition, when being involved in, consider the transverse force F of trailing wheel 7 and 8 _rChange easily owing to be involved in or owing to be involved in to differ surely and obtain the transverse force F that expects by turning to of front- wheel 5 and 6 _r, shown in the step S224 among Fig. 5, can be target diversion torque T with turn to torque settings according to the basis that turns to torque M T.

In addition, when vehicle 1 travels on rasping road, shown in the step S242 among Fig. 9, can be by reducing the transverse force F of trailing wheel 7 and 8 _rDifferential value dF _r(its have comparatively big noise) turns to the share of the calculating of torque for convergence, perhaps by this share being set at 0 (in other words, by based on trailing wheel 7 with less noise and 8 transverse force F _rCalculate convergence and turn to torque), can in the influence of removing rasping road as much as possible, preferably calculate convergence and turn to torque.

In addition, when vehicle 1 is quickening or is slowing down, shown in the step S243 among Fig. 9, can be by reducing the transverse force F of trailing wheel 7 and 8 _r(itself owing to quicken or slow down and significantly change) turns to the share of the calculating of torque for convergence, perhaps by this share being set at 0 (in other words, by the transverse force F based on trailing wheel 7 and 8 _rDifferential value dF _r(its can owing to quickening and slowing down and significantly change) calculates convergence and turns to torque), can when removing the influence of quickening or slowing down as much as possible, preferably calculate convergence and turn to torque.

In addition, when the foe and aft force of execution such as ABS control controlled on vehicle 1, shown in the step S244 among Fig. 9, can be by reducing the transverse force F of trailing wheel 7 and 8 _r(itself because foe and aft force control and significantly change) turns to the share of the calculating of torque for convergence, perhaps by this share being set at 0 (in other words, by the transverse force F based on trailing wheel 7 and 8 _rDifferential value dF _r(it can significantly not change owing to foe and aft force control) calculated convergence and turns to torque), can in the influence of removing foe and aft force control as much as possible, preferably calculate convergence and turn to torque.

In addition, when the vertical load the control of execution such as suspension is controlled, shown in the step S245 among Fig. 9, can be by reducing the transverse force F of trailing wheel 7 and 8 _r(itself since vertically load control and significantly change) turn to the share of the calculating of torque for convergence, perhaps by this share being set at 0 (in other words, by transverse force F based on trailing wheel 7 and 8 _rDifferential value dF _r(it can not controlled and significantly change owing to vertically loading) calculated convergence and turned to torque), can in the influence that the vertical load of removal is controlled as much as possible, preferably calculate convergence and turn to torque.

In addition, if vehicle velocity V is unusual, can be by reducing the transverse force F of trailing wheel 7 and 8 _r(it significantly changes) turns to the share of the calculating of torque for convergence, perhaps by this share being set at 0 (in other words, by the transverse force F based on trailing wheel 7 and 8 _rDifferential value dF _r(it can significantly not change) calculated convergence and turns to torque), can when removing the unusual influence of vehicle velocity V as much as possible, preferably calculate convergence and turn to torque.

Incidentally, in the aforementioned embodiment, based on turning to torque M T and target diversion torque T that front- wheel 5 and 6 is turned to.But even under the situation of the described so-called active steering that turns to of wherein being carried out front- wheel 5 and 6 based on deflection angle θ by actuator, be under the overshoot state if turn to, aspect that also can be identical with aforementioned operation is carried out to turn to and is obtained aforementioned various advantage.

(3) modified example

Then, with reference to Figure 15 and Figure 16, will give an explaination to the modified example of the electric power steering apparatus in the present embodiment 10.

(3-1) first modified example

Figure 15 is the summary construction diagram of basic structure of first modified example that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.As shown in figure 15, in first modified example, except being used to make the electric power steering apparatus 10 that front- wheel 5 and 6 turns to, also be provided for the electric power steering apparatus 50 that trailing wheel 7 and 8 is turned to.

Electric power steering apparatus 50 for example is the rack pinion electric power steering apparatus, and it is provided with: electrical motor 55, and it is used to produce makes the assisted diversion power that trailing wheel 7 and 8 turns to and is used for assisted diversion power is applied to steering shaft 52 by not shown reducing gear; And rack and pinion mechanism 56.

In first modified example of this structure,, trailing wheel 7 and 8 is turned to if different to the steering direction that steering handwheel 11 carries out with the direction that the wheel flutter that is applied by electrical motor 15 turns to front- wheel 5 and 6 by chaufeur.At this moment, aforementioned basis turns to torque to output to from ECU 30 as target torque to be used to electrical motor 15 that front- wheel 5 and 6 is turned to.

By trailing wheel 7 and 8 is turned to, can change the yaw moment of vehicle 1 side.That is, in the embodiment that explains referring to figs. 1 to Figure 14, the target diversion torque T of electrical motor 15 changes the yaw moment that turns to by convergence being turned to torque T set not.But, in first modified example, change the yaw moment of vehicle 1 side.Even change the yaw moment of vehicle 1 side like this, can prevent as mentioned above that also turning to of vehicle from vibrating and yaw vibrates (particularly, preventing that both are with phase resonance opposite each other) coupled to each other.This can cause the convergence of the vibration of front-wheel 5 and 6.That is the constringent convergence that improves vehicle 1 simultaneously that can turn in raising.

In addition, because be that target diversion torque T turns to front- wheel 5 and 6, so have the advantage that impression can variation that turns to of chaufeur by turning to torque settings according to the basis that turns to torque M T.

(3-2) second modified example

Figure 16 is the summary construction diagram of basic structure of second modified example that the embodiment of Vehicular steering control apparatus of the present invention conceptually is shown.As shown in figure 16, in second modified example, be provided with and be used to make the active steering equipment 61 that front-wheel 5 turns to and be used to active steering equipment 62 that front-wheel 6 is turned to.Active steering equipment 61 and 62 target rudder angle δ based on the front-wheel of exporting from ECU 30 5 _LTarget rudder angle δ with front-wheel 6 _RFront- wheel 5 and 6 is turned to, make the rudder angle of front-wheel 5 become δ _LAnd the rudder angle of front-wheel 6 becomes δ _R

In second modified example, as mentioned above, if judgement turns to the overshoot state that is in, then with target rudder angle δ _LAnd δ _RBe set at and make front- wheel 5 and 6 toe-ins.

As mentioned above, by front- wheel 5 and 6 is set at toe-in, can change the turning power C of front- wheel 5 and 6 _PThereby, to change the vibration performance value of front-wheel 5 and 6.Thus, can prevent as mentioned above that turning to of vehicle from vibrating and yaw vibrates (particularly, preventing that both from resonating with phases opposite) coupled to each other.This can cause the convergence of the vibration of front-wheel 5 and 6.That is the constringent convergence that improves vehicle 1 simultaneously that can turn in raising.

The invention is not restricted to previous embodiment, and can do not depart from of the present invention can the Accessory Right claim and whole specification sheets in carry out various changes under the situation of the essence that discloses and spirit.Also the intention Vehicular steering control apparatus that will be referred to these changes is included in the technical scope of the present invention.

Claims (27)

1. Vehicular steering control apparatus comprises:

The steering effort bringing device, it is used for basic steering effort is applied to front-wheel at least; With

The transverse force detecting device, it is used to detect described front-wheel and the every person's of trailing wheel transverse force,

If the ratio of the described transverse force of the described transverse force of described trailing wheel and described front-wheel becomes the ratio of the yaw vibration that may cause in the vehicle, then described steering effort bringing device will be restrained steering effort and will be applied to described front-wheel, and described convergence steering effort makes described front-wheel steering on the direction of described yaw vibration convergence.

2. Vehicular steering control apparatus according to claim 1, wherein, (i) if turn to be in and rotate or the incision state by what the chaufeur of described vehicle carried out, then compare with the situation that the described transverse force of described front-wheel does not become the described ratio that may cause the described yaw vibration in the described vehicle with the described transverse force of described trailing wheel, described steering effort bringing device will apply as the steering effort of the described front-wheel of making of described convergence steering effort to the neutral directional steering of front-wheel steering, if and (ii) turn to be in and return or inverted status by what the described chaufeur of described vehicle carried out, then do not become the situation that may cause the described yaw vibration in the described vehicle with the described transverse force of described trailing wheel with the described transverse force of described front-wheel and compare, described steering effort bringing device will apply as the steering effort of the described front-wheel of making of described convergence steering effort to the end directional steering of front-wheel steering.

3. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device applies basic steering effort to control the rudder angle of described front-wheel.

4. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device is based on the basic steering effort that turns to torque to control to be applied to described front-wheel according to the steering operation of the chaufeur of described vehicle.

5. Vehicular steering control apparatus according to claim 1, wherein, if the described ratio of the described transverse force of the described transverse force of described trailing wheel and described front-wheel greater than predetermined first threshold values, then described steering effort bringing device applies described convergence steering effort.

6. Vehicular steering control apparatus according to claim 5, wherein, if the ratio of the rudder angle of the described transverse force of described trailing wheel and described front-wheel greater than predetermined second threshold values, then described steering effort bringing device applies described convergence steering effort.

7. Vehicular steering control apparatus according to claim 1, wherein, if the ratio of the rudder angle of the angle of roll of described vehicle and described front-wheel greater than predetermined the 3rd threshold values, then described steering effort bringing device applies described convergence steering effort.

8. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each.

9. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device is revised described convergence steering effort according to the speed of described vehicle.

10. Vehicular steering control apparatus according to claim 9, wherein, if described vehicle travels on rasping road, then described steering effort bringing device reduces described convergence steering effort.

11. Vehicular steering control apparatus according to claim 10, wherein, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, if described vehicle travels on described rasping road simultaneously, then compare, reduce the share of described differential value of the described transverse force of described trailing wheel with the situation that described vehicle travels on ordinary road.

12. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device calculates described convergence steering effort based on the kinematic model of described vehicle on in-plane.

13. Vehicular steering control apparatus according to claim 12, wherein, described steering effort bringing device based on reflected the input that turns to torque, the described kinematic model of described vehicle on described in-plane calculate described convergence steering effort.

14. Vehicular steering control apparatus according to claim 1, wherein, if at least one in the absolute value of the absolute value of deflection angle and turning velocity is equal to or less than predetermined the 4th threshold values, then described steering effort bringing device reduces described convergence steering effort.

15. Vehicular steering control apparatus according to claim 1, wherein, if at least one in the absolute value of the absolute value of deflection angle and turning velocity is equal to or greater than predetermined the 5th threshold values, then described steering effort bringing device reduces described convergence steering effort.

16. Vehicular steering control apparatus according to claim 1, wherein, if the steering direction that the chaufeur of described vehicle carries out is opposite with the direction that described steering effort bringing device applies basic steering effort, then described steering effort bringing device reduces described convergence steering effort.

17. Vehicular steering control apparatus according to claim 1, wherein, if the steering direction that the chaufeur of described vehicle carries out is opposite with the direction that described steering effort bringing device applies basic steering effort, then described steering effort bringing device applies basic steering effort to described trailing wheel.

18. Vehicular steering control apparatus according to claim 16, wherein, turning under the situation of vibration, even the described steering direction that the described chaufeur of described vehicle carries out is opposite with the described direction that described steering effort bringing device applies basic steering effort, described steering effort bringing device still applies described convergence steering effort.

19. Vehicular steering control apparatus according to claim 1, wherein, if described vehicle is changed the foe and aft force control of the foe and aft force of described vehicle, then described steering effort bringing device reduces described convergence steering effort.

20. Vehicular steering control apparatus according to claim 19, wherein, if described vehicle is not carried out described foe and aft force control, then described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, and

If described vehicle is carried out described foe and aft force control, then described steering effort bringing device calculates described convergence steering effort based in the described differential value of the described transverse force of the described ratio value of the described transverse force of described trailing wheel and described trailing wheel each, compares the share of the described ratio value of the described transverse force that reduces described trailing wheel simultaneously with the situation of not carrying out described foe and aft force control.

21. Vehicular steering control apparatus according to claim 20, wherein, if carry out the described foe and aft force control of the described foe and aft force that changes described vehicle, then described steering effort bringing device does not apply described convergence steering effort, and

After described foe and aft force control finishes, described steering effort bringing device at first applies the described convergence steering effort that the described differential value based on the described transverse force of described trailing wheel calculates during scheduled time slot, and then applies the described convergence steering effort that the described share of the described ratio value of the described transverse force by increasing described trailing wheel in time gradually calculates.

22. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, reduces the described share of described ratio value of the described transverse force of described trailing wheel simultaneously more along with the increase of the acceleration/accel of described vehicle or deceleration/decel.

23. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device calculates described convergence steering effort based in the differential value of the described transverse force of the ratio value of the described transverse force of described trailing wheel and described trailing wheel each, simultaneously in the scheduled time slot after the acceleration/accel of described vehicle or deceleration/decel begin to change, keep stable situation to compare with described acceleration/accel and deceleration/decel, reduce the share of described ratio value of the described transverse force of described trailing wheel.

24. Vehicular steering control apparatus according to claim 1, wherein, if change the load control of the vertical load of described front-wheel, then described steering effort bringing device reduces described convergence steering effort.

25. Vehicular steering control apparatus according to claim 1, wherein, if if exist in the possibility that is involved in the described vehicle or described being involved in taken place, then described steering effort bringing device reduces described convergence steering effort.

26. Vehicular steering control apparatus according to claim 1, wherein, described steering effort bringing device involving vibrations eigenwert modifier, it is used for may causing in the described transverse force of described trailing wheel the vibration performance value of the described front-wheel of change under the vibrative situation of described front-wheel.

27. Vehicular steering control apparatus according to claim 26, wherein, each of described front-wheel that described vibration performance value modifier can make the described front-wheel that is positioned at the right side and be positioned at the left side turns to different rudder angles respectively, and

If the described transverse force of described trailing wheel may cause described front-wheel to produce vibration, then described vibration performance value modifier applies the steering effort as described convergence steering effort, is used to make described front-wheel towards the directional steering that makes described toe-in of front wheel.

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